With the increasing development of technologies and manufacturing processes, thin film transistor liquid crystal displays (TFT-LCDs) have become the mainstream device of flat panel displays. The core component of a TFT-LCD is a display panel, and the liquid crystal display panel mainly comprises a color filter (CF) substrate, an array substrate, and a liquid crystal layer between the color filter substrate and the array substrate. In a cell-assembling process, a sealant is used to bond the four sides of the two substrates and to seal the liquid crystal layer between the two substrates as well.
With the research and development on narrow-frame display devices, the layout of the display panel becomes more and more compact, which places higher demands on the alignment accuracy of the color filter substrate and the array substrate. If the alignment accuracy of the color filter substrate and the array substrate is insufficient, the position where the sealant is applied becomes quite close to the liquid crystal, making it easy for the sealant to contact with the liquid crystal and contaminate the liquid crystal, thereby affecting the quality of the product.